fix(client): 连接后延迟用内核 urltest 实测 + 侧栏套餐到期日接真

- 延迟:TCP 探针在隧道开启时会被路由进隧道而测不到(显示 —)。改为连接后
  (phase==on)取内核 statsStream 的 urltest delayMs 最小正值(代理真实 RTT),
  未连接时仍用节点 TCP 探针。连接页 _SpeedRow/_NodePill/_CurrentNodeCard
  与统计页平均延迟统一此口径。
- plan_badge_card(侧栏)接 me.expiresAt 显示真实到期日(原只显示「有效期至」
  无日期);account_page 之外漏改的最后一处。

flutter analyze 0 error;114 tests passed。

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

client/lib/screens/connect_page.dart

@@ -2,6 +2,7 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 
+import '../bridge/vpn_bridge.dart';
 import '../core/responsive/form_factor.dart';
 import '../l10n/app_text.dart';
 import '../models/node.dart';
@@ -34,6 +35,11 @@ class ConnectPage extends ConsumerWidget {
     final stats = ref.watch(vpnStatsProvider).valueOrNull;
     final down = _mbps(stats?.downloadSpeed);
     final up = _mbps(stats?.uploadSpeed);
+    // 延迟来源:连接后用内核 urltest 实测(代理真实 RTT,TCP 探针被隧道吞掉时仍准);
+    // 未连接时用节点 TCP 探针 ping。0/无 → 显示 —。
+    final livePing = conn.phase == VpnPhase.on ? _bestUrltest(stats) : node.ping;
+    final pingLabel = livePing > 0 ? '${livePing}ms' : '—';
+    final latencyValue = livePing > 0 ? '$livePing' : '—';
 
     final caption = switch (conn.phase) {
       VpnPhase.off => t.capOff,
@@ -65,8 +71,8 @@ class ConnectPage extends ConsumerWidget {
     final infoChildren = <Widget>[
       if (isFree)
         QuotaCard(quota: quota, t: t, onWatchAd: () => ref.read(quotaProvider.notifier).watchAd()),
-      if (conn.phase == VpnPhase.on) _SpeedRow(t: t, node: node, down: down, up: up),
-      _CurrentNodeCard(t: t, node: node, smart: smart, showLabel: isWide, onTap: onOpenNodes),
+      if (conn.phase == VpnPhase.on) _SpeedRow(t: t, down: down, up: up, latency: latencyValue),
+      _CurrentNodeCard(t: t, node: node, smart: smart, pingLabel: pingLabel, showLabel: isWide, onTap: onOpenNodes),
     ];
 
     final statusTrailing = Text(
@@ -104,7 +110,7 @@ class ConnectPage extends ConsumerWidget {
                     style: PangolinText.caption.copyWith(color: c.danger, fontWeight: FontWeight.w500)),
               ),
             ],
-            _NodePill(t: t, node: node, smart: smart),
+            _NodePill(t: t, node: node, smart: smart, pingLabel: pingLabel),
             if (isFree) ...[
               const SizedBox(height: 24),
               SizedBox(
@@ -114,7 +120,7 @@ class ConnectPage extends ConsumerWidget {
             ],
             if (conn.phase == VpnPhase.on) ...[
               const SizedBox(height: 16),
-              _SpeedRow(t: t, node: node, down: down, up: up),
+              _SpeedRow(t: t, down: down, up: up, latency: latencyValue),
             ],
           ]),
         ),
@@ -199,13 +205,20 @@ class ConnectPage extends ConsumerWidget {
 String _mbps(double? bytesPerSec) =>
     bytesPerSec == null ? '—' : (bytesPerSec * 8 / 1000000).toStringAsFixed(1);
 
+/// 内核 urltest 各出站中的最小正延迟(ms);无则 0。
+int _bestUrltest(VpnStatsEvent? s) {
+  if (s == null) return 0;
+  final ds = s.urltestResults.where((r) => r.delayMs > 0).map((r) => r.delayMs);
+  return ds.isEmpty ? 0 : ds.reduce((a, b) => a < b ? a : b);
+}
+
 /// 实时速率行(连接成功时显示;来自内核 statsStream 实时数据)。
 class _SpeedRow extends StatelessWidget {
-  const _SpeedRow({required this.t, required this.node, required this.down, required this.up});
+  const _SpeedRow({required this.t, required this.down, required this.up, required this.latency});
   final AppText t;
-  final Node node;
   final String down;
   final String up;
+  final String latency;
 
   @override
   Widget build(BuildContext context) {
@@ -213,7 +226,7 @@ class _SpeedRow extends StatelessWidget {
     final metrics = [
       (PangolinIcons.arrowDown, t.download, down, 'Mb/s'),
       (PangolinIcons.arrowUp, t.upload, up, 'Mb/s'),
-      (PangolinIcons.zap, t.latency, node.ping > 0 ? '${node.ping}' : '—', 'ms'),
+      (PangolinIcons.zap, t.latency, latency, 'ms'),
     ];
     return Row(children: [
       for (var i = 0; i < metrics.length; i++)
@@ -258,12 +271,14 @@ class _CurrentNodeCard extends StatelessWidget {
     required this.t,
     required this.node,
     required this.smart,
+    required this.pingLabel,
     required this.showLabel,
     required this.onTap,
   });
   final AppText t;
   final Node node;
   final bool smart;
+  final String pingLabel;
   final bool showLabel;
   final VoidCallback onTap;
 
@@ -272,8 +287,8 @@ class _CurrentNodeCard extends StatelessWidget {
     final c = context.pangolin;
     final title = smart ? t.smartSelect : node.localizedName(t.lang);
     final sub = smart
-        ? '${node.localizedName(t.lang)} · ${node.pingLabel}'
-        : '${node.localizedSub(t.lang)} · ${node.pingLabel}';
+        ? '${node.localizedName(t.lang)} · $pingLabel'
+        : '${node.localizedSub(t.lang)} · $pingLabel';
     return Material(
       color: c.surface,
       shape: RoundedRectangleBorder(
@@ -314,17 +329,18 @@ class _CurrentNodeCard extends StatelessWidget {
 
 /// 桌面连接页节点胶囊（[zap] 智能选择 · 节点名 · 延迟ms）。
 class _NodePill extends StatelessWidget {
-  const _NodePill({required this.t, required this.node, required this.smart});
+  const _NodePill({required this.t, required this.node, required this.smart, required this.pingLabel});
   final AppText t;
   final Node node;
   final bool smart;
+  final String pingLabel;
 
   @override
   Widget build(BuildContext context) {
     final c = context.pangolin;
     final label = smart
-        ? '${t.smartSelect} · ${node.localizedName(t.lang)} · ${node.pingLabel}'
-        : '${node.localizedName(t.lang)} · ${node.pingLabel}';
+        ? '${t.smartSelect} · ${node.localizedName(t.lang)} · $pingLabel'
+        : '${node.localizedName(t.lang)} · $pingLabel';
     return Container(
       padding: const EdgeInsets.symmetric(horizontal: 14, vertical: 6),
       decoration: BoxDecoration(